New appliances will not run when genny is charging thru Trace sw4024

riverdog

Hello All,
I have been on an offgrid system since 1989 and all went well until we had a housefire 2 years ago. As a result we got a new washer, dryer, and dishwasher. I am still on the same HUP batteries and same Trace 4024 inverter as before the fire but now when I start the genny to charge the batteries the 3 mentioned appliances will not run.
With the genny off they work fine but not when it is running, no matter if the inverter is in float mode or charge, no go. It always worked fine with the older appliances, I am stumped, any ideas out there would be appreciated.
Footnote: the house was also rewired and code required the new type breakers. The genny is an 8000 watt harbor freight but a similar size honda genny made no difference.

inetdog

Re: New appliances will not run when genny is charging thru Trace sw4024

riverdog wrote: »

Hello All,
I have been on an offgrid system since 1989 and all went well until we had a housefire 2 years ago. As a result we got a new washer, dryer, and dishwasher. I am still on the same HUP batteries and same Trace 4024 inverter as before the fire but now when I start the genny to charge the batteries the 3 mentioned appliances will not run.
With the genny off they work fine but not when it is running, no matter if the inverter is in float mode or charge, no go. It always worked fine with the older appliances, I am stumped, any ideas out there would be appreciated.
Footnote: the house was also rewired and code required the new type breakers. The genny is an 8000 watt harbor freight but a similar size honda genny made no difference.

How is the generator set up to charge the batteries? Is it using the Trace as the Charge Controller? Is the problem that the inverter will not start or that it just will not power those loads? Is there any diagnostic indication on the Trace when this happens (like battery voltage out of range for example)?
When you had the fire, were the batteries left in a partially discharged state for a long time, leading to sulphation? Not likely since they will power the appliances with the genny off, but still worth looking at.

vtmaps

Re: New appliances will not run when genny is charging thru Trace sw4024

Just a wild guess... there is some sort of transfer switch that is wired wrong. When the generator comes on the trace stops inverting (as it should), but the generator output is not switched over to the appliances.

One more thought... modern appliances with computer controls may be intolerant of out of spec voltage or frequency provided by generator. The trace may put out better power than the generator.

--vtMaps

Photowhit

Re: New appliances will not run when genny is charging thru Trace sw4024

Are these all 120v appliances? other than these the rest of the 120v loads are fine?

RCinFLA

Re: New appliances will not run when genny is charging thru Trace sw4024

If you plug the appliance(s) directly into the generators do they work?

When gen is connected to AC2in its output is passed through directly to ACout of SW4024 (after SW is locked to it). Charging is a parallel pick off and depending on what charge rate you have setup and will automatically back down its draw for charging when output load demands more of the maximum set AC2in current.

Even if you have the max AC2in set low the inverter will switch from chargng to sourcing to make up any short fall in available amperage to ACout (up to the maximum of 33 amps). This is a good thing when your generator can't supply the peak load.

This all assumes the inverter is locked onto the generator. This is a solid green light, not blinking.

The inverter will follow the freq and voltage of the generator when it is locked onto generator (within SW spec range). If gen is off freq or voltage the appliance may not like it. Again the first test I would do is to see if the gen alone will run the appliances.

If the SW4024 is locked to generator you can read its voltage and freq on the SW display. It must be lock on with a solid green light.

Volvo Farmer

Re: New appliances will not run when genny is charging thru Trace sw4024

No help here but I can't help but be impressed that your batteries have lasted twenty three years. Been considering some of those myself and a data point like that helps me make a decision.

vtmaps

Re: New appliances will not run when genny is charging thru Trace sw4024

Volvo Farmer wrote: »

No help here but I can't help but be impressed that your batteries have lasted twenty three years. Been considering some of those myself and a data point like that helps me make a decision.

He didn't say he had the same batteries for 23 years. He said he had the same batteries now as he had before the fire two years ago.
--vtMaps

Volvo Farmer

Re: New appliances will not run when genny is charging thru Trace sw4024

AAH. My mistake.

riverdog

Re: New appliances will not run when genny is charging thru Trace sw4024

Thank you all for your wise input. I plugged the washer and dryer straight into the 120v receptacle (with the house still plugged in also) on the Harbor Freight genny and started it. At first it was charging the batteries as it should and running both appliances. After a few minutes I went to check and the washer and dryer both were stopped and displaying "Call Service", So I unplugged them from the first genny and tried them in a Honda genny, again they ran a while then shut down. When the genny is off they run fine thru the inverter. This leads me to think the new appliances are somehow not compatible with genny power.
The HUP batteries are actually the second set of Hups I have had and before them I was on L-16's not to mislead on the durability of the HUPs
There is no diagnostic indication on the inverter.
All other 120v things work fine.

inetdog

Re: New appliances will not run when genny is charging thru Trace sw4024

riverdog wrote: »

This leads me to think the new appliances are somehow not compatible with genny power.

When you mentioned the fire, we forgot that it probably meant new appliances as well as new wiring! Not sure what about genny power might be making the appliances unhappy. Maybe voltage variation or frequency variation, both of which would not occur with the inverter. New appliances run by computers instead of mechanical timers bring in a brand new load of problems.
If the appliances do not even start when plugged in normally, it sounds like the problem there could be a transfer switch or other wiring detail that connects them only to the inverter.

(Both ideas suggested by vtmaps back in post #3)

vtmaps

Re: New appliances will not run when genny is charging thru Trace sw4024

inetdog wrote: »

New appliances run by computers instead of mechanical timers bring in a brand new load of problems.
If the appliances do not even start when plugged in normally, it sounds like the problem there could be a transfer switch or other wiring detail that connects them only to the inverter.

As per post #3 in this thread. --vtMaps

RCinFLA

Re: New appliances will not run when genny is charging thru Trace sw4024

That fact that two generators are yielding the same issue on the appliances would suggest you might be overloading the generators. I would say all bets are off on Harbor Freight gen but Honda's generators are usually pretty good.

Electric driers draw about 20-25 amps at 240 volts (about 5 kW) when the heater is on. It cycles on and off during clothes drying. The motor in washing machine has high starting surge current, particularly when going into spin rinse cycle.

Either alone or together, along with any charging and other loads on SW4024 have a high probability of at least momentarily overloading generator. The SW will suppliment some of the overload but if the generator bogs down and drops in voltage or frequency the inverter will release from generator. If the appliance concurrently shuts down due to voltage slump then the heavy loads that caused the problem no longer exist so the SW4024 will reconnect to generator. You come out to find everything seeming fine except the tripped off appliances not working.

solarvic

Re: New appliances will not run when genny is charging thru Trace sw4024

Is your dryer a gas dryer with an electric motor, or an all electric dryer? I think that would overload your system if it is an all electric dryer.
I doubt that your new appliances are having any trouble with the quality of power you get from the generator. My family accross the road from me have a 6000 watt chinese diesel generator that probably doesn,t have the cleanest power and her late model Sears (LG) fridge runs fine and she has spun out the clothes before with the LG frontloader and it run just fine. freezer computers, tv run just fine. If they could get the pump to run they would have it made. Solarvic

riverdog

Re: New appliances will not run when genny is charging thru Trace sw4024

My dryer is gas with electric motor. When plugged into the house receptacle with genny running and charging the dryer will try to start but rarely can, if it does start it will stop before too long. The washer will begin it's cycle and shut down before 5 min. or so.
So anytime the genny is involved the appliances are shutting down or not starting at all.

vtmaps

Re: New appliances will not run when genny is charging thru Trace sw4024

riverdog, do you have a kill-a-watt? If so, use it to check the frequency of your generator. --vtMaps

BB.

Re: New appliances will not run when genny is charging thru Trace sw4024

Check the Hot to Neutral voltage at the appliances (under load). If you have a bad neutral connection anywhere between the genset (especially if this is a 120/240 VAC genset) and the appliances, you can get some strange results.

Basically, the neutral sort of "floats" between the two hots--You will get a steady 240 VAC on Hot to Hot, but you may get 160 VAC from one phase of Hot to Neutral and 80 VAC between the other phase's Hot to Neutral.

The "heavy" 120 VAC load will "collapse its Hot to Neutral, while the other Hot to Neutral goes over voltage.

-Bill

RCinFLA

Re: New appliances will not run when genny is charging thru Trace sw4024

If your gen is a 240 split phase then the 120vac outputs will not supply full gen power unless it has a 240/120 switch that parallels the two 120vac winding together.

I know Honda and likely Harbor Freight rate their generator wattage on peak power, not continuous power. If you are also half side 120vac loading a 240/120 vac generator you can draw about 55% to 60% of their continuous rated power before you get too much voltage slump from winding resistance loss.

bwoltz

Re: New appliances will not run when genny is charging thru Trace sw4024

While I'd be concerned about the neutral issue, I suspect that part of the problem is the appliances.. The fact that they go into weird conditions, implies that that they've suffered a brown out that has disrupted their normal function.. The newer appliances probably have a microprocessor that controls the main functions of the appliances as they are cheaper overall. The brown out is caused buy the starting one of the electric motors in an appliance. The genset cannot handle the surge of the motor starting and sags the voltage (and probably the frequency) The trace 4024 can supply up to 75 amps (IIRC) for a short time with almost no sag from it output and it's recovery is much faster than a generator.


The older appliances probably used mechanical timer to perform the functions. Nice thing about mechanical timers is that they remember through brown outs..

What's the solution?

1. Bigger generator.. Maybe one of the newer inverter types?
2. Find appliances that don't suffer from brown outs.
3. Only run the appliances of the Trace..
4. You might be able to tune the Trace to get you what you want..

On the trace you can set the max charge amps and max gen set output. With a little playing you can still get reasonable charge rate out of the Genset and still supply the house power. The first thing that I'd try is to set the max genset out to the same value or only a couple amp higher than the max charge current. This will let the Trace charge at the rate you need but cut current draw when the house load increases. This will work only to some extent as from what I've seen the control loop that the trace uses to change charging rates is slow.. About 1 or 2 seconds.. You can try cutting the max charge rate and gen input in half and see if the appliances start to function normally. This is a better situation for the Genset.. Have a light load on them (as apposed to low load or heavy load allow then to handle surges best.). I run my shop off a 12.5kw Generac when running a inverter TIG welder.. By itself the TIG welder will keep resetting. If I run on the lathe and give the generator a nice low load, the tig welder works fine..


Bruce

RCinFLA

Re: New appliances will not run when genny is charging thru Trace sw4024

If the gen set is a 6kW you should limit the Max AC2in current to something less then 25 amps. You might have to play with the number, bringing it down until the issue goes away. The SW4048 reacts faster then the generator to load surge but it still take some time, 100 mseconds or so, to react.

If you set the max ACin2 low enough it will help protect the generator so it does not slump in voltage too much which may be enough to keep the appliance from tripping off. Remember the generator is the reference and the SW will follow it down until the drop exceeds the SW set limits at which point the SW releases from generator.

For surges greater then 25 amps the short fall is made up by battery power through the SW inverter. With a 25 amp AC2in limit you should be able to supply surges of 25 amps (or less if lower setting on generator AC2in is necessary to keep it from slumping) plus the 33 amps from inverter for a total of 58 amps. You can actually go a little higher then this because the inverter will puts out more then 33 amps for a short period. There is some voltage slump if you surge the inverter over 33 amps.